Apparatus for attaching inserts to ducts



Dec. 6, 1966 K. E. GURITZ APPARATUS FOR ATTACHING INSERTS T0 DUGTS Filed April 20, 1964 INVENTOR.

KENNETH E. GUR/TZ A TTOR/VE Y5 United States Patent M 3,289,287 APPARATUS FOR ATTACHING HNSERTS TU DUQTS Kenneth E. Guritz, Gurlee Mfg. (10., 160 W. York St,

West Chicago, Ill.

Filed Apr. 20, 1964, Ser. No. 361,194 10 Claims. (Cl. 29-24352) This invention relates to apparatus for attaching inserts to ducts and more particularly to apparatus for securing a tubular insert or collar to a sheet metal duct.

In modern building practice it has become customary to embed sheet metal ducts in the floors or ceilings of building structures as, for example, by setting the ducts in forms and pouring concrete or the like over and around them. Ducts of this sort are used for flow of warm air for heating as well as to provide conduits for carrying electrical wiring and the like.

In some cases, the ducts have been preformed with inserts or collars which open into.the ducts and which project outwardly therefrom a sufiicient distance to be exposed through the concrete after it is poured. However, in many cases it becomes necessary to provide additional inserts in the ducts after pouring of concrete or similar aggregate around them. This is done by drilling or cutting away the concrete or aggregate to expose the duct surface, by drilling a hole through the duct and by attaching an insert thereto.

In this operation the attaching of the insert must be done from the outside of the duct and through the opening therein so that it is a blind operationand is diflicult to perform. The preferred method of attachment is by swedging over the lower rim portion of the insert to grip the duct tightly thereby providing both a mechanically secure joint and a fluid tight joint between the insert and the duct. With inserts as heretofore constructed and with attaching apparatus as heretofore available this has been an extremely difficult operation.

It is accordingly one of the objects of the present invention to provide an attaching apparatus by means of which inserts can be readily and securely mounted on ducts after installation of the ducts. It will be apparent, of course, that the same apparatus could be used for mounting of inserts prior to installation.

Another object is to provide insert attaching apparatus in which the lower lip portion of an insert is rapidly swedged over to grip tightly and securely against the wall of a duct surrounding the opening in which the insert is mounted.

According to a feature of the invention, the insert lip is swedged over by two or more hammers pivotally mounted we head and oscillated rapidly while being turned to swedge over the lip on the insert.

According to another feature of the invention the apparatus is readily adjustable to accommodate inserts of different lengths.

The above and other objects and features of the invention will be more readily apparent from the following description when read in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a portion of a duct having inserts mounted thereon;

FIG. 2 is an'axial section with parts in elevation show: ing the apparatus of the invention in operative position in association with an insert and a duct;

FIG. 3 is a bottom view of the apparatus of FIG. 2 taken along section 33 in FIG. 2;

FIG. 4 is a partial section showing a completed duct and insert assembly;

FIG. 5 is a partial view onthe line 5-5 of FIG. 2 showing the means for preventing turning of the insert during installation; and

3,23%,27 Patented Dec. 6, 1%66 FIG. 6 is an elevation of an insert with parts broken away.

As shown in FIG. 1, the inserts of the present invention are adapted to be installed on a generally rectangular section ducting as shown at 10 which may be embedded in a concrete floor or ceiling, or in a similar floor or ceiling formed of other aggregate materials which are poured in place. The duct may be of any desired size, but is formed with a flat top, as shown at 11, in which inserts indicated generally at 12 may be mounted at desired spaced positions. Each of the inserts, as best seen in FIG. 6, is formed of a tube or collar internally threaded at its outer end at 13 and formed at its lower end with a reduced lip 14- joined to the main body of the inserts with a square shoulder 15. Preferably the lower edge of the lip is beveled, as indicated at 16, at its outer surface for a purpose to appear hereinafter. According to one of the features of the present invention, each insert is formed in its upper edge with a notch or opening 17 defined by square axially extending shoulders, as seen in FIGS. 5 and 6. During installation of the insert, this notch cooperates with a complementary lug on the installing apparatus to hold the insert against turning, as will appear more fully hereinafter.

For installing an insert in a duct the duct is first formed with an opening of a size to receive the lip 14 with the shoulder 15 resting on the upper surface of the duct, as seen in FIG. 2. The installing apparatus comprises an annular body 18 having a reduced lower end extension 19 to fit into the upper end of the insert and defining a shoulder to rest on the upper edge of the insert. At one side, the body is formed with a projecting lug 21 complementary to the notch 17 to fit into the insert so that the body will be held against rotation relative to the insert.

A hammer head is carried by the body and comprises an elongated tubular shaft portion 22 which fits rotatably in a central bore in the body and an enlarged head portion 23 which is of a size to pass through the insert. The head portion 23 is formed at diametrically opposite points with radially extending slots 24 in which hammers 25 are pivoted.

As best seen in FIGS. 2 and 3, the hammers are in the form of rectangular bars pivoted intermediate their ends on pivot rods 26 and of such a length that when in a generally horizontal position their pivot ends will project beyond the head 23 to engage the lower edge of the lip 14-. At their outer ends the hammers are formed with recesses having inner edges 2'7 of relatively large radius which will initially engage the skirt of the insert to tend to flow it outwardly. At their outer edges the hammers terminate in portions of smaller radius 28 which will tend to curl up the lip portion into a configuration substantially as shown in FIG. 4. In the completed assembly, as shown in FIG. 4, the lip portion 14 is bent upwardly in an arcuate curve with the bevel edge 16 resting substantially fiat against the inner surface of the duct upper Wall 11 to provide a tight seal and tight mechanical gripping engagement between the insert and the duct. Furthermore, with this configuration of the lip, no sharp edges are left which might cut wire or similar pieces being drawn through the ducts.

The hammers are operated by a hammer shaft 29 which extends slidably through the head shaft 22. The hammer shaft at its lower edge will engage the inner ends of the hammers 25 so that when it is vibrated axially, it will cause the hammers to rock about their pivots in a series of rapid hammer blows to swedge the lip of the insert. The hammer shaft is also preferably connected to the hammers by means of links 31 which, as best seen in FIG. 3, lie in slots in the inner ends of the hammers and extend into mating slots in the hammer shaft. When the hammer shaft is pulled upwardly these links will tilt the hammers to a generally vertical position to swing the outer ends thereof to a downward position radially within the outline of the head so that the head and hammers can readily be withdrawn through the insert at the completion of an installing operation. In order to prevent relative rotation between the shaft and the head which might tend to strain the links 31 the head shaft is formed in its upper end with an elongated slot 32 and the hammer shaft 29 carries a pin 33 which is slidable vertically in the slot. This will enable the hammer shaft to be moved vertically relative to the head but without relative rotation therebetween.

In order to adjust the apparatus for different lengths of inserts the head shaft 22 is externally threaded, as shown, and receives a threaded split collar 34. The collar can be turned to any desired position of adjustment and can be locked by a lock screw 35 to hold it securely in adjusted position on the head. The collar normally rests on a bearing ring 36 which in turn rests on top of the body 18 so that the vertical position of the head relative to the body is fixed but the head and body may rotate freely relative to each other. The body is preferably formed with a handle 37 by which it may conveniently be held during operation and the upper end of the hammer shaft 29 is formed, as shown at 38, for attachment to a suitable power tool. Various different types of power tools may be used which are available on the market and which will cause the hammer shaft to rotate while at the same time vibrating rapidly in an axial direction.

In use with a proper sized opening cut in the duct, either as an exposed duct or through an opening cut in the material in which it is embedded, an insert may be placed with the flange 14 thereon extending through the opening in the duct in the position shown in FIG. 2. The apparatus may be adjusted for the length of the insert used by adjustment of the collar 34 and then with the hammer shaft pulled up to retract the hammers the head may be inserted through the insert with the body 18 resting on top of the insert and with the lug 21 fitting into the notch 17, as shown. The hammer shaft may then be lowered to the position shown in FIG. 2 wherein its lower end rests on the inner ends of the hammers and with the pin 33 in the slot 32. An appropriate tool may then be attached to the upper end of the hammer shaft and may be turned on to cause the hammer shaft to rotate while vibrating at a high rate of speed in an axial direction.

The vibration of the hammer shaft will cause the hammers to strike the lower edge of the flange 14 a rapid series of blows with the edge of the flange engaging the radial portion 27 of the hammers to be flared outward. At the same time the head will be turning so that the hammers will traverse the entire circumference of the flange to peen it over. As finally completed, the flange will be bent over, as shown in FIG. 4, so that the insert is secured rigidly to the duct.

At this time, the tool may be removed or may be left on the hammer shaft and be pulled upwardly to retract the hammers into the head 23. The apparatus may now be removed through the installed insert Whose installation is completed.

While one embodiment of the invention has been shown and described herein, it will be understood that it is illustrative only and not to be taken as a definition of the scope of the invention, reference being had for this purpose to the appended claims.

What is claimed is:

1. Apparatus for attaching inserts to ducts comprising an annular body adapted to rest on the upper edge of an insert, a tubular hammer head extending rotatably through the body, radially extending hammers pivoted on the lower end of the head on axes transverse to the head, and being swingable in planes including the axis of the head, the outer ends of the hammers normally projecting radially beyond the head to engage and deform the skirt of an insert, the hammers being pivotal to positions in which they are substantially withdrawn within the head whereby the head and hammers can pass through an insert, and a hammer shaft extending slidably through the hammer head to engage the inner ends of the hammers and move them about their pivots.

2. The apparatus of claim 1 in which the outer ends of the hammers are formed in their upper surfaces with recesses having inner edges of relatively large radius which initially engage the skirt of an insert to flow it outwardly and outer edges of relatively small radius which curl and compact the skirt against the inner surface of a duct.

3. The apparatus of claim 1 including means to prevent relative rotation of the head and shaft while permitting relative lengthwise movement thereof.

4. The apparatus of claim 1 including lost motion means connecting the hammers to the shaft to pivot the hammers to said withdrawn positions within the head when the shaft is moved lengthwise out of the head.

5. The apparatus of claim 1 including a stop collar adjustably secured on the head and rotatably engaging the annular body to limit lengthwise movement of the head through the body.

6. The apparatus of claim 1 in which the head comprises a tubular shank portion extending through the body and an enlarged head portion formed with radially extending slots in which the hammers are pivotally movable.

'7. Apparatus for attaching inserts to ducts comprising a tubular body to rest on the outer edge of an insert, a tubular head carried by the body to extend into the insert to a point adjacent to its other end, radially extending hammers carried by the head for swinging in planes including the axis of the head and with their outer ends normally projecting beyond the head to engage and deform the other end of the insert, the hammers being mounted for withdrawal into the head whereby they can pass through the insert, and operating means for the hammers extending through the body and the head.

8. The apparatus of claim 7 in which the operating means comprises a shaft slidable axially through the body and head, and means connecting the shaft to the hammers to withdraw them into the head when the shaft is moved out of the body and head.

9. For use with a tubular duct insert having an axially extending skirt at one end of less thickness than the insert and joined to the insert through an external flat shoulder, apparatus for securing the insert to a duct comprising an annular body having a reduced end portion extending into the insert and an annular shoulder engaging the other end of the insert, a tubular hammer head extending rotatably through the body, radially extending hammers pivoted to the head adjacent to' the skirt on axis transverse to the head and with their outer ends projecting therebeyond to engage and deform the skirt, a hammer shaft extending slidably through the head to engage and actuate the hammers, and interengaging parts on the body and the insert to prevent relative rotation therebetween.

10. The device of claim 9 in which the interengaging parts comprise an axially extending notch in the other end of the insert and a projection on the annular shoulder on the body fitting into the notch.

References Cited by the Examiner UNITED STATES PATENTS 805,868 11/ 1905 Marshall 72-393 988,054 3/1911 Wiet 72393 1,511,773 10/ 1924 Riedesel 29275 1,982,400 11/ 1934 Riemenschneider 7 2-393 2,142,017 12/ 1938 Riemenschneider 72393 2,306,619 12/ 1942 Flachbarth 29200 2,324,468 7/ 1943 Brickman 29-200 3,211,474 12/1965 Johnson 285-205 JOHN F. CAMPBELL, Primary Examiner.

OMAS EAGER, Examiner. 

1. APPARTUS FOR ATTACHING INSERTS TO DUCTS COMPRISING AN ANNULAR BODY ADAPTED TO REST ON THE UPPER EDGE OF AN INSERT, A TUBULAR HAMMER HEAD EXTENDING ROTATABLY THROUGH THE BODY, RADIALLY EXTENDING HAMMERS PIVOTED ON THE LOWER END OF THE HEAD ON AXES TRANSVERSE TO THE HEAD, AND BEING SWINGABLE IN PLANES INCLUDING THE AXIS OF THE HEAD, THE OUTER ENDS OF THE HAMMERS NORMALLY PROJECTING RADIALLY BEYOND THE HEAD TO ENGAGE AND DEFORM THE SKIRT OF AN INSERT, THE HAMMERS BEING PIVOTAL TO POSITIONS IN WHICH THEY ARE SUBSTANTIALLY WITHDRAWN WITHIN THE HEAD WHEREBY THE HEAD AND HAMMERS CAN PASS THROUGH AN INSERT, AND A HAMMER SHAFT EXTENDING SLIDABLY THROUGH THE HAMMER HEAD TO ENGAGE THE INNER ENDS OF THE HAMMERS AND MOVE THEM ABOUT THEIR PIVOTS. 